B1280

MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1280: Left Side Junction Block ECU Communication Stop
B1280 - Left Side Junction Block ECU Communication Stop

DESCRIPTION

This DTC is detected when communication between the instrument panel J/B (driver side J/B ECU) and network gateway ECU stops for more than 10 seconds.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK FUSE (MPX-B, D/C CUT)

(a) Remove the MPX-B from the engine room No. 1 relay block.

(b) Measure the resistance of the fuses.

Standard:

Below 1 Ohms

NG -- REPLACE FUSE
OK -- Continue to next step.

2. CHECK WIRE HARNESS (COWL SIDE JUNCTION BLOCK LH - BATTERY AND BODY GROUND)





(a) Disconnect the PL and PA J/B connectors.

(b) Measure the resistance and voltage of the wire harness side connectors.

Standard resistance:





Standard voltage:





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

3. CHECK RESISTANCE OF COMMUNICATION LINE





(a) Disconnect the V3 ECU connector.

(b) Disconnect the LC J/B connector.

(c) Disconnect the b7 switch connector.

(d) Measure the resistance of the wire harness side connectors.

Standard resistance:





Result:





C -- REPAIR OR REPLACE HARNESS AND CONNECTOR

B -- REPLACE COWL SIDE JUNCTION BLOCK LH AND WIRE HARNESS CONNECTOR

A -- REPLACE COWL SIDE JUNCTION BLOCK LH